Alkyl alpha-alkylsulfonylacrylates and polymers and polymers thereof



United States Patent O ALKYL WALKYLSULFONYLACRYLATES AND iFOLYMERS AND POLYMERS THEREOF Hubert M. Hill, Kingsport,

Kodak Company, New Jersey No Drawing. Application April 7, 1955, Serial No. 500,012

10 Claims. (Cl. 260-793) Tenn, assignor to Eastman Rochester, N. Y., a corporation of wherein R and R1 represent alkyl groups containing from 1 to 4 carbon atoms, e. g. methyl, ethyl, propyl, isopropyl, butyl, sec. butyl, etc. groups. The above defined compounds are valuable intermediates for the preparation of resinous homopolymers and copolymers thereof which are characterized by having high softening points and good solubility in common volatile organic solvents. Some of the polymers are useful as adhesives, while certain other copolymers, for example, those with acrylonitrile can be molded, extruded, or coated from their solutions to give shaped articles and films having high heat distortion temperatures or they can be spun into tough and dyeable fibers.

It is, accordingly, an object of the invention to provide a new class of unsaturated monomeric compounds. Another object is to provide resinous polymers of the same. Another object is to provide a process for preparing the new compounds. Other objects will become apparent hereinafter.

In accordance With my invention, I prepare the alkyl alpha-alkylsulfonylacrylates defined above by reacting an alkyl ester of an alkylsulfonylacetic acid with formaldehyde or an equivalent thereof such as paraformaldehyde, trioxymethylene, etc. in the presence of a basic catalyst, preferably in an aqueous or alcoholic reaction medium. The reaction may be represented by the following general equation:

wherein R and R1 are as above defined. The temperature of the reaction can be varied from about 30 to 120 (3., but preferably from 50 to 100 C. Pressures above atmospheric can be employed. A continuous process wherein the reactants are added continuously or in increments and the reacted mixture is continuously removed and the product isolated can also be used. The

proportions of the principal reactants can vary so that a slight excess of that required of one or the other may be present, but advantageously approximately equimolar proportions are employed. The basic catalyst may be pyridine, quino-line, etc., but preferably piperidine, in an amount of about from 0.5 to 5%, based on the total weight of the principal reactants.

Suitable intermediate alkyl esters of alkylsulfonylacetic acids include methyl methylsulfonylacetate, methyl ethylsulfonylacetate, methyl propylsulfonylacetate, methyl Patented Oct. 1, 1957 isopropylsulfonylacetate, m e th y l butylsulfofiylacetate, methyl sec. butylsulfonylacetate, methyl tert. butylsulfonylacetate, ethyl methylsulfonylacetate, ethyl ethylsulfonylacetate, ethyl propylsulfonylacetate, ethyl butylsulfonylacetate, propyl methylsulfonylacetate, propyl ethylsulfonylacetate, propyl propylsulfonylacetate, propyl butylsulfonylacetate, butyl methylsulfonylacetate, butyl ethylsulfonylacetate, butyl propylsulfonylacetate, butyl butylsulfonylacetate, and the like. The above compounds may be prepared, for example, by the general method described in Beilsteins Hand. Org. Chem., 4th ed., vol. III, page 248 (1921), by refluxing approximately equimolar proportions of an alkali metal salt of an alkanesulfinic acid containing from 1 to 4 carbon atoms, e. g. methanesulfinic acid, ethanesulfinic acid, propanesulfinic acid, isopropanesulfinic acid, butanesulfinic acid, etc. and an ester of chloroacetic acid in a reaction medium of a saturated, monohydroxy aliphatic alcohol containing from 1 to 4 carbon atoms e. g. ethanol, propanol, isopropanol, butanol, etc., and separating the ester product from the reaction mixture by conventional methods of separation such as extraction, distillation, etc. For example, ethyl methylsulfonylacetate may be prepared by this method from the sodium salt of methanesulfinic acid and the ethyl ester of chloroacetic acid in ethanol.

The polymerizations of the new compounds of the invention alone, with themselves or with one or more other unsaturated, polymerizable monomers containing a CH=C group, but preferably a vinyl group CH2=CH, are accelerated by heat, by actinic light and by polymerization catalysts which are known to promote the polymerization of vinyl and other unsaturated organic compounds, for example, peroxides such as benzoyl peroxide, acetyl peroxide, tertiary butyl hydroperoxide, hydrogen peroxide, etc., persulfates such as ammonium persulfate, sodium persulfate, potassium persulfate, perborate, sodium perborate, water-soluble salts of potassium perborate, etc., the perphosphoric acid, boron trifiuoride, and the like. The organic peroxide catalysts are especially suitable. Mixtures of catalysts can be employed. An activating agent such as sodium bisulfite, sodium metabisulfite, etc. can be used, if desired, in conjunction With the polymerization catalysts. Also chain regulators can also be used such as an alkyl mercaptan such as hexyl, octyl, lauryl, dodecyl, myristyl merca-ptans, etc. Ordinarily, the polymerization catalyst is employed in a quantity of about from 0.01 to 3%, preferably from 0.2 to 2.0%, based on the total weight of the monomers to be polymerized. The activating agent and chain regulator are present in amount of about the same order as the polymerization catalyst.

The polymerizations can be carried out in mass or dispersed in a nonsolvent for the monomers, the particles of dispersed monomer being very small (emulsion) or relatively large (bead or granular). For emulsion polymerization, any nonsolvent for the monomers can be employed, Water being especially advantageous. The monomer or mixture of monomers can be advantageously emulsified in the water'using emulsifying agents such as salts of higher fatty acids (e. g., sodium or potassium stearate, palmitate, etc.), ordinary soaps, salts of higher fatty alcohol sulfates (e. g., sodium or potassium acetyl sulfate, sodium or potassium lauryl sulfate, sodium or potassium stearyl sulfate, etc.) salts of aromatic sulfonic acids (e. g. sodium or potassium salts of alkylnaphthalene sulfonic acids, etc.) and higher molecular weight quaternary ammonium salts (e. g., dimethylbenzylphenyl ammonium chloride, etc.). For head or granular polymerization relatively poor dispersing agents such as starch, methylated starch, gum arabic polyvinyl alcohol,

partly hydrolyzed polyvinyl acetate, gelatin sodium glycolate and finely divided magnesium carbonate, etc., can be employed. Mixtures of dispersing agents can be used. In the polymerizations wherein the monomers are dispersed in nonsolvents, the dispersions can be facilitated by stirring, shaking or tumbling the polymerization mixtures. Continuous methods of polymerization can also be employed.

Suitable other unsaturated, polymerizable compounds for preparing the copolymers of the invention include preferably those containing the basic CH2==CH group, for example, vinyl esters of carboxylic acids (e. g., vinyl acetate, vinyl butyrate, vinyl stearate, vinyl trifluoroacetate, vinyl benzoate, etc.), vinyl alkyl ketones (e. g., methyl vinyl ketone, ethyl vinyl ketone, trifiuoromethyl vinyl ketone, etc.), vinyl alkyl ethers (e. g., methyl vinyl ether, butyl vinyl ether, etc.), vinyl sulfonamides (e. g., vinyl sulfonamide, N-methyl vinyl sulfonamide, etc.), vinyl halides (e. g., vinyl chloride, vinyl bromide, and vinyl fluoride), vinyl alkyl sulfones (e. g., vinyl methyl sulfone, vinyl ethyl sulfone, etc.), vinyl urethanes (e. g., vinyl methyl urethane, vinyl ethyl urethane, etc.), cyclic vinyl imides (e. g., vinyl succinimide, vinyl phthalimide, etc.), acrylic acid and its anhydride, amide, N-alkylamide, nitrile, and the methyl, ethyl, butyl, benzyl and phenyl esters thereof, butadiene, etc. Still other suitable unsaturated, polymerizable compounds which can be copolymerized with our new monomers include methacrylic acid and its anhydride, amide, N-alkyl amides, nitrile, and the methyl, ethyl, butyl, benzyl and phenyl esters, vinylidene dichloride, vinylidene chloride-fluoride, alkyl esters of maleic and fumaric acids such as methyl maleate, methyl fumarate, fumaronitrile, cisand trans-fi-cyano and carboxamido-rnethyl' acrylate, and the like.

The copolymers of the invention can contain variable amounts of each comonomer and are obtained with starting polymerization mixtures containing from 25% to 75 by weight of the new unsaturates and from 75% to 25% by weight of the above mentioned other unsaturated organic compounds. The copolymers have been found to contain substantially the same proportion of substituents as employed in the polymerization mixtures. The temperature of the polymerizations can be varied widely. Where a polymerization activating agent is employed, the polymerization will take place ata' temperature as low as C. However, the preferred temperature range for the polymerizations is from 25 C. to 130 C.

The following examples will serve to illustrate further our new unsaturated compounds, polymers thereof, and the manner of preparing the same.

Example 1 g. of phosphorus pentoxide (P205) were added, and the water from the reactionwas removed by azeotropic distillation. When the mixture became anhydrous,- the remaining solvent was removed by distillation and the residue was vacuum distilled to yield" 63 g. (0.35 mol.) of ethyl a-methylsulfonylacrylate,

a colorless liquid boiling at 150152- C./ 5 mm. pressure. In place of the ethyl methylsulfonylacetatein the aboveexample, there may be substituted an equivalent amount of methyl ethylsulfonylacetate to give methyl a-ethylsulfonylacrylate, or. an equivalent amount-of methyl n butylsulfonylacetate to give methyl oz-n-butylsulfonyh acrylate,v these compounds being generally similar poly-. merizable, colorless liquids.

Example 2 A mixture of 152 g. (1.0 mol.) of methyl methylsulfonylacetate, CH3SO2.CH2.CO2.CH3, 30 g. (equiv. to 1.0 mol. of HCHO) of trioxymethylene and 400 cc. of ethanol was reacted in the presence of piperidine and the product isolated in the same manner as described in Example 1. A yield of g. (0.7 mol.) of methyl amethylsulfonylacrylate, CH2=C(-SO2CH3)CO2CH3, a colorless liquid having a boiling point of -137 C./5 mm. pressure, was obtained.

Example 3 A mixture of 90 g. (0.5 mol.) of ethyl ethylsulfonylacetate, C2H5SO2.CH2.CO2.C2H5, 15 g. (equiv. to 0.5 mol. of HCHO) of paraformaldehyde and 200 cc. of ethanol was heated in the presence of piperidine and the product isolated in the same manner as described in Example 1. A yield of 65 g. (0.34 mol.) of ethyl a-ethylsulfonylacrylate, CH2=C(-SO2C2H5)CO2C2H5, a colorless liquid distilling at -162 C. at 5 mm. pressure, was obtained.

Example 4 10 g. of ethyl p-methylsulfonylacrylate and 0.2 g. of I Example '5 A mixture of 10 g. of methyl a-methylsulfonylacrylate, 10 g. of acrylonitrile, 0.2 g. of potassium persulfate and 0.2 g. of sodium bisulfite was added to 100 cc. of water. Polymerization began in a few minutes and was completed on standing after several hours. The resinous copolymer obtained wasfound to consist of approximately 50% by weight of methyl a-methylsulfonylacrylate, the remainder of the resin molecule being acrylonitrile. It had a softening point of about C. and was soluble in dimethylformamide from which solution it was spinnable into flexible, dyeable fibers having good tensile strength and excellent elongation.

In place of the methyl u-methylsulfonylacrylate, there can be substituted in the above example a like amount of methyl a-ethylsulfonylacrylate or a like amount of ethyl a-ethylsulfonylacrylate to give resinous copolymers having generally similar percentage compositions and characteristics and also being capable of beingspun into excellent fibers from their solutions in solvents such as dimethylformamide gamma-butyrolactone, ethylene carbonate, and the like 'solvents.

Example 6 5 g. of ethyl a-ethylsulfonylacrylate, 5 g. of styrene and 0.1 g. of benzoyl peroxide were heated together in a sealed tube at 60 C. for a period of 24 hours. A clear, hard, moldable resin was obtained. Analysis showed it to be a copolymer containing approximately 50% by weight of ethyl a-ethylsulfonylacrylate, the remainder of the polymer being styrene.

The amounts of the reactants in the above example may be varied widely and stillresult in good moldable copolymers, for example, there may be employed only 2.5 g. of the ethyl ot-ethylsulfonylacetate and 7.5 g. of the styrene, or only 2.5 g. of the styrene and 7.5 g. of the ethyl aethylsulfonylacetate.

Example 7 5 g. of methyl a-methylsulfonylacrylate, 5 g. of ethyl a-ethylsulfonylacrylate and 0.2 g. of benzoyl peroxide were heated together at 60 C. for 24 hours. The resultant moldable copolymer contained approximately 50% by weight of each of the above acrylate. It was readily soluble in acetone, from which solution it was coatable into tough, flexible sheets.

By proceeding as set forth in the above examples, other generally similar homopolymers and copolymers may be prepared containing, in the case of the copolymers, from 25 to 75% by weight of one or more of any of the mentioned alkyl ot-alkylsulfonylacrylates coming within the invention and from 75 to 25% by weight of any of the mentioned other unsaturated polymerizable monomeric compounds. All of the polymers of the invention are soluble in one or more common solvents such as acetone, acetonitrile, dimethylformamide, dimethylacetamide, ethylene carbonate, 'y-butyrolactone, N-methyl-Z- pyrrolidone, ethylene cyanohydrin, and the like. From their viscous dopes or solutions in solvents of this kind, the polymers can be extruded, for example, through a suitable spinneret into a cabinet or cell where the solvent is evaporated off to give monofilaments which can be spun to yarn. Wet spinning processes are also operable.

. Such viscous dopes can also be coated on a film-forming surface of, for example, metal or glass, the solvent evaporated and the resulting film stripped from the film-forming surface. Films or sheets of this kind are useful for making flexible photographic supports. Both the molding compositions and the dope compositions may, if desired, contain modifying materials such as plasticizers, fillers, coloring materials, etc. Where the polymer is molded, an extrusion, injection or compression molding technique may be employed.

What I claim is:

1. A copolymer consisting of from 25 to 75 by weight of an alkyl u-alkylsulfonylacrylate having the general formula:

wherein R and R1 each represents an alkyl group containing from 1 to 4 carbon atoms, and from 75 to 25% by weight of a diiferent polymen'zable compound containing a CH2=CH group.

2. A copolymer of from 25 to 75% by weight of methyl a-methylsulfonylacrylate and from 75 to 25 by weight of acrylonitrile.

3. A copolymer of from 25 to 75 by weight of ethyl ot-ethylsulfonylacrylate and 75 to 25 by weight of styrene.

4. A copolymer of from 25 to 75% by weight of methyl a-ethylsulfonylacrylate and from 75 to 25% by weight of acrylonitrile.

5. A copolymer of from 25 to by weight of methyl a-n-butylsulf0nylacrylate and from 75 to 25 by weight of acrylonitrile.

6. A process for preparing a copolymer of an alkyl a-alkylsulfonylacrylate having the general formula:

0 CHFC-A-0 R Boa-R CH2: CH-

group.

7. The process for preparing a coplymer of methyl u-methylsulfonylacrylate and acrylonitrile which comprises heating in the presence of a peroxide polymerization catalyst a mixture comprising as the sole polymerizable components from 25 to 75 by weight of methyl vt-methylsulfonylacrylate and from 75 to 25 by Weight of acrylonitrile.

8. The process for preparing a copolymer of ethyl ot-ethylsulfonylacrylate and styrene which comprises heating in the presence of a peroxide polymerization catalyst a mixture comprising as the sole polymerizable components from 25 to 75 by weight of ethyl u-ethylsulfonylacrylate and from 75 to 25% by weight of styrene.

9. The process for preparing a coplymer of methyl u-ethylsulfonylacrylate and acrylonitrile which comprises heating in the presence of a peroxide polymerization catalyst a mixture comprising as the sole polymerizable components from 25 to 75 by weight of methyl u-ethylsulfonylacrylate and from 75 to 25 by weight of acrylonitrile.

10. The process for preparing a copolymer of methyl a-nbutylsulfonylacrylate and acrylonitrile which comprises heating in the presence of a peroxide polymerization catalyst a mixture comprising as the sole polymerizable components from 25 to 75 by weight of methyl a-n-buty1su1fony1acry1ate and from 75 to 25 by weight of acrylonitrile.

2,694,699 Laaksa Nov. 16, 1954 

1. A COPOLYMER CONSISTING OF FROM 25 TO 75% BY WEIGHT OF AN ALKYL A-ALKYLSULFONYLACRYLATE HAVING THE GENERAL FORMULA: 